A process for texturizing polycrystalline silicon (hereinafter also "polysilicon" or "poly") is discussed in an article entitled "Rugged Surface Poly-Si Electrode and Low Temperature Deposited Si3N4 for 64 Mb and Beyond STC DRAM Cell" authored by M. Yoshimaru et al, Oki Electric Industry Co., Ltd., VLSI R&D Laboratory pp. 550-1, Higashiasakawa, Hachioji, Tokyo 193, Japan. In this article, using a poly deposition temperature of 570 degrees Celsius causes the poly layer surface to become rugged (or textured). The article claims that applying this technique to form a storage node cell plate of a dynamic random access memory's (DRAM) storage stacked capacitor, results in an increase of the cell plate's surface area of up to 2.5 times that of a standard stacked capacitor cell (STC).
Two main drawbacks with this method are: 1) the temperature must be precisely controlled (within .+-.3 degrees C. of 570.degree. C.) during deposition to form the rugged poly surface; and 2) subjecting the rugged poly to temperatures above 570 degrees C. in subsequent process steps can cause the rugged surface to flatten out.
In the present invention, a stable and uniform texturized poly surface is developed that will retain its textured surface throughout implementation of conventional DRAM fabrication processes.